We will continue to prepare purified cholesterol esterase for the production of antibodies and will continue our studies on the localization of cholesterol esterase in the intestinal mucosa, particularly by electron microscopy. Also, in reference to the intestinal mucosa, we will use isolated intestinal cells to study cholesterol esterification and the incorporation of these esters into newly synthesized lipoproteins. This investigation will include a study of conditions for the release of these lipoproteins into the medium. Cholic acid analogues will be coupled to a non-absorbable resin carrier and these complexes tested for the prevention of the absorption of cholesterol. Also, in this area we will continue our studies on the mechanism of action of fibers as inhibitors of cholesterol absorption.